Modular offers you the ability to build your own synthesizer, the way you want to. At the same time, modular is a great tool for learning how analog subtractive synthesis works.

By separating each synthesis process, modules can be connected in any way. You are no longer limited to synthesizers designed by others, you are now in full control of your sound. This is the beauty and power of modular synthesis.
Modular looks, acts, and sounds like a hardware modular synthesizer to give you the familiarity and features that musicians want such as pulse width modulation, oscillator sync, 4 pole ladder filters, and 1v/oct filter tracking.
Traditional modular systems cost $$$$ where modular is free. In-app purchases give you access to advanced modules. Owning a module means you own as many as you can fit in the modular rack. Do you want to build a monster 6 oscillator synth? You can.

Features:

Analog sound

Bandlimited oscillators

Oversampled filters

Beautiful graphics

Dynamic workspace

Intuitive navigation

Controls that give detailed values such as filter frequency in Hz and oscillator tuning in semitones

Minimal menu interface

Keyboard with 10 octave range

Arpeggiator

In app help and tutorials

Audiobus support

Soundcloud export

CoreMIDI support

Record live performance

Email recordings

Import / export patches via iTunes file sharing

Background Audio

And it’s free! There’s an IAP that is very competitively priced. Download it and take a look.